Hey there everyone!
So I'm basically a french student and I've recently started a huge project with two friends of mine, entirely coded in Python language. So here's the idea: we want to create a space orbital mechanics simulator in 3d, and our main goal is to use the Panda3d library. The main issue is that coding 3d games/programs implies the use of OOP (object-oriented programming). And I have no idea how to use this. I've made my best to understand the sample files given on the panda3d wiki, but it's still very hard to me. Which is why I would be extremely gratefull if somebody could help me with the 3d part of the coding .Regarding the physics of it, I think we have enough knowledge to achieve those without worry.
Oh and by the way we created a github page so that if you're interested you can follow us during our programming odyssey : https://github.com/l3alr0g/Python-Orbital-Mechanics
PS: Please don't mind my english, I'm not bilingual

I'd say your English is better than a lot of native speakers who try to express themselves here. So basically, you'll be applying the exact same techniques you'd be applying in 2D, in 3D:

• Represent at least the position, mass, and velocity of each body, except in 3D, with 3D vector quantities for the position and velocity, rather than in 2D.
  
• Repeatedly execute time steps. In each step, compute the forces that each body exerts on each other body using Newton's Law of Universal Gravitation. Because F=ma, you can calculate the acceleration experienced by each body, then use simple kinematics to compute its new velocity, then its new position.
  

That should really be it. Let me know if I can clarify either of those.